package com.shaiMiMi;

public class DataTypeChangeHelper {
	//long类型转成byte数组
	  public static byte[] longToByte(long number) {
	        long temp = number;
	        byte[] b = new byte[8];
	        for (int i = 0; i < b.length; i++) {
	            b[i] = new Long(temp & 0xff).byteValue();// 将最低位保存在最低位
	            temp = temp >> 8; // 向右移8位
	        }
	        return b;
	    }

	    //byte数组转成long
	    public static long byteToLong(byte[] b) {
	        long s = 0;
	        long s0 = b[0] & 0xff;// 最低位
	        long s1 = b[1] & 0xff;
	        long s2 = b[2] & 0xff;
	        long s3 = b[3] & 0xff;
	        long s4 = b[4] & 0xff;// 最低位
	        long s5 = b[5] & 0xff;
	        long s6 = b[6] & 0xff;
	        long s7 = b[7] & 0xff;

	        // s0不变
	        s1 <<= 8;
	        s2 <<= 16;
	        s3 <<= 24;
	        s4 <<= 8 * 4;
	        s5 <<= 8 * 5;
	        s6 <<= 8 * 6;
	        s7 <<= 8 * 7;
	        s = s0 | s1 | s2 | s3 | s4 | s5 | s6 | s7;
	        return s;
	    }

	/**
	     * 注释：int到字节数组的转换！
	     *
	     * @param number
	     * @return
	     */
	    public static byte[] intToByte(int number) {
	        int temp = number;
	        byte[] b = new byte[4];
	        for (int i = 0; i < b.length; i++) {
	            b[i] = new Integer(temp & 0xff).byteValue();// 将最低位保存在最低位
	            temp = temp >> 8; // 向右移8位
	        }
	        return b;
	    }

	    /**
	     * 注释：字节数组到int的转换！
	     *
	     * @param b
	     * @return
	     */
	    public static int byteToInt(byte[] b) {
	        int s = 0;
	        int s0 = b[0] & 0xff;// 最低位
	        int s1 = b[1] & 0xff;
	        int s2 = b[2] & 0xff;
	        int s3 = b[3] & 0xff;
	        s3 <<= 24;
	        s2 <<= 16;
	        s1 <<= 8;
	        s = s0 | s1 | s2 | s3;
	        return s;
	    }

	    /**
	     * 注释：short到字节数组的转换！
	     *
	     * @param s
	     * @return
	     */
	    public static byte[] shortToByte(short number) {
	        int temp = number;
	        byte[] b = new byte[2];
	        for (int i = 0; i < b.length; i++) {
	            b[i] = new Integer(temp & 0xff).byteValue();// 将最低位保存在最低位
	            temp = temp >> 8; // 向右移8位
	        }
	        return b;
	    }

	    /**
	     * 注释：字节数组到short的转换！
	     *
	     * @param b
	     * @return
	     */
	    public static short byteToShort(byte[] b) {
	        short s = 0;
	        short s0 = (short) (b[0] & 0xff);// 最低位
	        short s1 = (short) (b[1] & 0xff);
	        s1 <<= 8;
	        s = (short) (s0 | s1);
	        return s;
	    }
}
